They are all important, but you can't do them all at the same time, so a well structured and training plan should emphasize one key aspect at at any particular block of time (theory of periodicity).

However I will say that if you want to keep it relatively casual then frequency is probably the most important thing. Just getting out and doing something each day gets you a long way. Then duration to enhance endurance, then lastly intensity to improve speed and power.

2) Frequency: the more times you perform a skill, the better you get at it. Without recycling what is now a cliché, it’s the old “10000 hours” thing.

3) Duration: One must be able to perform Work. Physics defines Work as when an object is moved over a distance by an external force. For our purposes, it is a load performed for a period of time. The longer you can execute a skill, be it squats or running or skating, the more work you are performing and the greater your capacity for higher workloads becomes.

Think of all these as building the foundation for Intensity

4) Intensity: Though it comes in fourth, that doesn’t mean it is necessarily least important. But without proper skills development, one’s intensity is almost useless. Would you advocate super hard skate sprints if someone hasn’t developed the proper technique? Should a beginning boxer pound a heavy bag with all out intensity if they haven’t yet learned how to properly execute a punch? Should a track athlete run high-intensity intervals before the muscles and tendons in their legs have been properly conditioned?

Finally, professor Stephen Seiler examined the ratio of high intensity training to the total of training for Olympic athletes spanning some twenty years and found that 90% of their training fell in the Zone 2 range, a very low-stress range. This shows clearly the role of intensity.

Consistency in your exercise plan will result in gradual improvements in strength and form, provided you pay attention to technique so as not to train yourself to use poor technique.

Intensity - the single greatest lesson I ever learned about aerobic intensive sports is that intervals are truly the best training technique. Years ago I participated in a local group bike ride weekly, and I met one of the riders who served as a coach for a local cycling club. In conversation I told him that my riding was nothing more than cross training for skating. He asked me some questions about skating and at some point I told him that I did not understand why all of the drills we did (do) for indoor short track are interval style. He told me that if you train for speed, distance will come. To that I replied "Huh" and he explained that for aerobically intense sports, if you focus your training on assorted intervals, you really will not need to train for distance if you're talking about marathon or even tri-athalon distances. He said that appropriate interval training will give you the aerobic capacity to ride, run, or skate the distance. That completely changed my perspective.

The studies show that across ALL sports the commonalities in the best practices filter down, and that overwhelmingly they show that athletes spend most of their time (80-90%) training at low intensity, ie < 80% max heart rate, zone 2, aerobic zone, <2mmol/ltr... or whatever you want to call it. Skating is no different at all.

The myth that you can do 5 minutes of intervals as a complete replacement for 1hr of easy aerobic work is absurd - it is the stuff that is out there to sell fitness magazines.

Yes you will get more "bang for your buck" with higher intensity, but that is less than half the picture. The higher energy system, lactate threshold are more responsive, but the improvements also flatten out after a relatively short period of repetition. You won't get any improvement in lactate threshold much past 1-2 years of training. By contrast the aerobic system can be built and improved year after year for as much as 10-15 years. Do you want the quickest return, or the best outcome? Because they are different questions.